Clean data function to ensure data is in proper format

[vitalielias]

There are currently some missing requirements for the metadata document structure and data preparation as outlined in the schema.

Mainly:

var	action
acquisition.dataset.entry.definition	To be assigned the value “acquisition_dataset”
acquisition.dataset.entry.datasetType	To be read from the folder name, such as “SEM Image”, SEM Image2”, “EDS”, “EBSD”, “BSE”, etc.
acquisition.dataset.entry.numberOfItems	The number of images in the folder, eg. If 719 images are there in SEM Image, the value should be 719
acquisition.dataset.entry.instrument.spot	Need to be deleted from the metadata if acquisition.dataset.entry.instrument.eBeam.beamCurrent.value is present (The mapping "acquisition.dataset.entry.instrument.spot":"Images.SEM Image.SliceImage.Beam.spot" not included in current map for ease)
acquisition.dataset.entry.images.entry.definition	To be assigned the value “acquisition_image”

Additionally:

• Check if all Booleans are marked properly. Instead of True and False, some values will be On, Off, yes or no. These need to mapped to True or False accordingly.
• The SEM/FIB Tomography metadata uses SI units, so there are no unit mappings for values.

A function should be created which takes the final metadata dictionary before writing it to JSON and makes the necessary changes.